The present invention relates to radiation detectors, and more specifically to radiation detectors that use a polymer dispersed liquid crystal cell.
Present radiation-detection technology is based on the fact that ionizing radiation, as it passes through matter, creates electrical charges. These electrical charges can be collected by applying an electrical field to the matter such that an electrical signal is derived. The type of detector chosen will depend upon the nature of the radiation, e.g. neutral versus charged particles, and the desired objective, e.g. the timing between events or the energy of a given event. For example, thalium activated sodium iodide single crystals are suitable for the measurement of low energy gamma-rays with low energy resolution, although it has poor timing measurement characteristics. For high energy-resolution measurements, a solid state single-crystal detector such as pure germanium can be used.
Currently available single crystal detectors must be kept at low temperatures during operation, e.g. 77K, which makes the use of cryogenic materials a necessity. Geiger-Muller type devices work at room temperature, but their applicability is limited. None of these radiation detectors are sufficiently flexible in size or shape. Film-badge type radiation detectors indicate exposure integrated over time, without providing any information about the energy of the incident radiation.
For these and other reasons, there is a need for a radiation detector that operates at ambient temperature and can be built simply and economically in a variety of sizes and shapes in order to accommodate different measuring methodologies.
Generally, and in one form, the present invention is a device for the measurement of radiant energy using a polymer dispersed liquid crystal cell.
In another form, the present invention is a device for the detection of ionizing radiation that uses a polymer dispersed liquid crystal cell and a light source that is optically oriented toward the cell. The cell is connected to an electrical signal generator, and a light detector capable of producing output is optically aligned with the light source. Finally, a computer is connected to the light detector to analyze the output from the light detector.
In yet another form, the present invention is a system of devices for the detection of ionizing radiation composed of two or more detection assemblies. Each assembly is made up of a polymer dispersed liquid crystal cell, a light source that is optically oriented toward the cell, an electrical signal generator that is connected to the cell, a light source that is capable of generating output that is optically aligned with the light source, and a computer that is connected to the light detector to analyze the output of the light detector.
In still another form, the present invention is a method for detecting ionizing radiation that includes the steps of creating a polymer dispersed liquid crystal cell, optically orienting a light source toward the cell, connecting the cell to an electrical signal generator, optically aligning a light detector capable of producing output with the light source, and attaching a computer to the light detector to analyze the output of the light detector.
Other features and advantages of the present invention shall be apparent to those of ordinary skill in the art upon reference to the following detailed description taken in conjunction with the accompanying drawings.